PCT Publications WO2008/151149, WO2010/06032, WO2011/150410, WO2011/150411, WO2012/061647, and WO2012/106560 disclose oils and methods for producing those oils in microbes, including microalgae. These publications also describe the use of such oils to make oleochemicals and fuels.
Tempering is a process of coverting a fat into a desired polymorphic form by manipulation of the temperature of the fat or fat-containing substance, commonly used in chocolate making.
Certain enzymes of the fatty acyl-CoA elongation pathway function to extend the length of fatty acyl-CoA molecules. Elongase-complex enzymes extend fatty acyl-CoA molecules in 2 carbon additions, for example myristoyl-CoA to palmitoyl-CoA, stearoyl-CoA to arachidyl-CoA, or oleyl-CoA to eicosanoyl-CoA, eicosanoyl-CoA to erucyl-CoA. In addition, elongase enzymes aslo extend acyl chain length in 2 carbon increments. KCS enzymes condense acyl-CoA molecules with two carbons from malonyl-CoA to form beta-ketoacyl-CoA. KCS and elongases may show specificity for condensing acyl substrates of particular carbon length, modification (such as hydroxylation), or degree of saturation. For example, the jojoba (Simmondsia chinensis) beta-ketoacyl-CoA synthase has been demonstrated to prefer monounsaturated and saturated C18- and C20-CoA substrates to elevate production of erucic acid in transgenic plants (Lassner et al., Plant Cell, 1996, Vol 8(2), pp 281-292), whereas specific elongase enzymes of Trypanosoma brucei show preference for elongating short and midchain saturated CoA substrates (Lee et al., Cell, 2006, Vol 126(4), pp 691-9).
The type II fatty acid biosynthetic pathway employs a series of reactions catalyzed by soluble proteins with intermediates shuttled between enzymes as thioesters of acyl carrier protein (ACP). By contrast, the type I fatty acid biosynthetic pathway uses a single, large multifunctional polypeptide.
The oleaginous, non-photosynthetic alga, Protetheca moriformis, stores copious amounts of triacylglyceride oil under conditions when the nutritional carbon supply is in excess, but cell division is inhibited due to limitation of other essential nutrients. Bulk biosynthesis of fatty acids with carbon chain lengths up to C18 occurs in the plastids; fatty acids are then exported to the endoplasmic reticulum where (if it occurs) elongation past C18 and incorporation into triacylglycerides (TAGs) is believed to occur. Lipids are stored in large cytoplasmic organelles called lipid bodies until environmental conditions change to favor growth, whereupon they are mobilized to provide energy and carbon molecules for anabolic metabolism.